Constantine VII Porphyrogenitus, with Romanus I and Christopher, AD 913-959. AV Solidus, 20mm, 4.41.

+ KEbOHTEI – ROM – Ah? dECPOTH Romanus I standing facing, wearing crown and loros and holding cross on globe, crowned by Christ, on r., wearing tunic and himation, and holding book of gospels.
XPISTOF ET COhST'AYGG'b Facing busts of Christopher, on left, and Constantine VII, on right, both crowned and wearing loros and and clamys and holding long patriarchal cross between them. 

Sear Byz 1744; DO 5 (same dies).

Extremely rare.

With permission of Numismatica Ars Classica auction 92, lot 997, May 2016.